moron - having a mental age between 8 and 12
dumb - slow to learn or understand; lacking intellectual acuity; lacking the power of human speech;
idiot - a person of subnormal intelligence
imbecile - retardation more severe than a moron but not as severe as an idiot
maniac, lunatic - an insane person
We throw these words around (as a society) all the time without regard to their original intent. Is this simply a case of forgiving the past and trying not to repeat those mistakes going forward? Where do we draw the line with allowing words to be used outside of their initial purpose?